A communication infrastructure for a
data processing apparatus, and a method of operation of such a communication infrastructure are provided. The communication infrastructure provides first and second switching circuits interconnected via a bidirectional link. Both of the switching circuits employ a multi-channel communication protocol, such that for each transaction a communication path is established from an initiating master interface to a target slave interface, with that communication path comprising m channels. The m channels comprise one or more forward channels from the initiating master interface to the target slave interface and one or more reverse channels from the target slave interface to the initiating master interface, and
handshaking signals are associated with each of the m channels. The bidirectional link comprises n connection lines, where n is less than m, the bidirectional link supporting a first communication path from the first switching circuit to the second switching circuit and a second communication path in an opposite direction from the second switching circuit to the first switching circuit. Control circuitry is used to
multiplex at least one forward channel of the first communication path and at least one reverse channel of the second communication path, with the
multiplexing being performed in dependence on the
handshaking signals associated with the channels to be multiplexed. This allows the 2m channels formed by the first and second communication paths to be provided by the n connection lines of the bidirectional link.